Cleaning and polishing cloth

ABSTRACT

This invention comprises a cleaning and polishing cloth for use on glass, plastic, enamel and lacquer surfaces. This cleaning and polishing cloth consists essentially of a cloth carrier to which a polishing and cleaning agent is bound by means of a binding agent. These polishing and cleaning agents are preferably porous oxide gels, preferably a synthetic alumina or silica gel having a particle volume of 0.8 to 2.9 m3/gm, and a particle size spectrum in the range of about 1.5 to 60 microns. This polishing and cleaning cloth does not mar scratch-sensitive surfaces.

[ 51 Jan. 23, 1973 1 CLEANING AND POLISHING CLOTH [75] Inventor: Peter Franz Feig, D638 Ober- Eschbach, Germany [73] Assignee: W. R. Grace & Co., New York,

[22] Filed: March 31, 1971 [21] Appl.No.: 130,004

[56] References Cited UNITED STATES PATENTS 2,947,016 8/1960 Thompson ..l5/l04.93 2,467,340 4/1949 Seymour ..252/317 X 3,579,464 5/1971 Rosen et a1. ..252/317 2,726,961 12/1955 Iler .....252/313 S FOREIGN PATENTS OR APPLICATIONS 1,396,429 3/1965 France ..l5/l04.93

Primary Examiner-Leon G. Machlin Att0rney--Michael J. McGreal and Kenneth E. Prince [57] ABSTRACT This invention comprises a cleaning and polishing cloth for use on glass, plastic, enamel and lacquer surfaces. This cleaning and polishing cloth consists essentially of a cloth carrier to which a polishing and cleaning agent is bound by means of a binding agent. These polishing and cleaning agents are preferably porous oxide gels, preferably a synthetic alumina or silica gel having a particle volume of 0.8 to 2.9 m /gm, and a particle size spectrum in the range of about 1.5 to 60 microns. This polishing and cleaning cloth does not mar scratch-sensitive surfaces.

10 Claims, N0 Drawings CLEANING AND POLISHING CLOTH BACKGROUND OF THE INVENTION This invention relates to a new polishing and cleaning cloth, and particularly to one useful for scratch sensitive surfaces. This invention additionally relates to the method of making such a polishing and cleaning cloth, as well as the method of cleaning and polishing surfaces, and particularly scratch sensitive surfaces such as glass, plastic, enamel or lacquer surfaces.

In the household as well as for industrial purposes, polishing agents are usually employed in the solid form' as loose powders, that is, as polishing chalks, scouring powders, and the like, or in the form of suspensions. Apart from these polishing agents, composite polishing materials such as emery papers, emery cloths or lapping wheels are known, wherein a particulate polishing agent is firmly combined with a carrier material consisting of a textile material or paper. For the production of the last named products, very hard abrasive materials, for example, silicon carbide, are used. For this reason, such emery cloths or emery papers produce a substantial abrasion on the surface which is often undesirable, particularly for the treatment of finished wood surfaces or the treatment of varnish priming coats. These polishingcloths are unsuitable for the treatment of any surfaces which are sensitive to scratching. And for the cleaning of such surfaces as glass plates, lacquered or enameled surfaces of motorcars or polished plastic surfaces, the known emery cloth products are fully unsuitable.

It is the object 'of the present invention to provide a cleaning cloth containing a polishing agent which has a superior cleaning and polishing power as compared to an ordinary cleaning cloth but does not cause abrasion on scratch-sensitive surfaces, so that damages due to scratching are eliminated.

It is also an object of this invention to set out a polishing and cleaning cloth for use on glass, plastic, lacquer or enameled surfaces.

It is further an object of this invention to disclose a method of producing a polishing and cleaning cloth comprising a cloth carrier having a porous oxide gel bound to the cloth.

It is additionally an object of this invention to set out a polishing and cleaning cloth comprising a cloth having a porous alumina or silica gel bound to the cloth.

Brief Summary of the Invention The subject of the present invention comprises a cleaning and polishing cloth for scratch-sensitive surfaces, in particular glass, plastic and lacquer surfaces, which comprises a carrier material to which a polishing agent is bound by means of a binding agent and which is characterized in that the polishing agent is a porous oxide gel, preferably a synthetic silica or alumina of the gel type, having an effective particle volume of about 0.8 to 2.9 em /g and a particle size spectrum in the range of about 1.5 to 60/u, which polishing agent is bound to the carrier material by a water-swellable polymer as binding agent substantially without penetration of the latter into the pores of the gel. This polishing cloth is used to polish and clean scratch-sensitive surfaces such as glass, plastic, enamel and lacquer surfaces.

DETAILED DESCRIPTION OF THE INVENTION It has surprisingly been found that the polishing cloth of the present invention, after wetting with water, easily removes residues of insects and other solids, e.g., oil, road materials and wax residues from motorcar windshields without the glass showing any visible traces of scratches. In the same manner, residues of insects can quickly and easily be removed from the enameled, lacquered or chromium-plated parts of motorcars without these sensitive surfaces being damaged. In the household, the polishing cloth of the invention is highly suitable for window cleaning, cleaning plastic counter tops or stainless steel or enameled appliances. Moreover, obstinate stains which are not or only with difficulty removable with the conventional soluble detergents, can easily be removed with the present cloth, since even soft surfaces such as glossy oil alkyd coatings do not become dull by scratching, and on the other hand dulled lacquer and plastic surfaces are not polished to gloss. Thus, it is possible without difficulty to remove with the present polishing cloth some pen, pencil or crayon lines, or black lines caused by rubber heels from doors, plastic floor coverings and the like. Even rough-fiber wallpapers painted with dispersion paints can be cleaned with the instant cloth without any damage to the wallpaper itself.

It is especially advantageous that the polishing cloth of the invention needs only be wetted with water before use, and that no powders or substances are required or given off during use on the surface being cleaned. Therefore, no traces are left which would have to be removed afterwards in a subsequent operation. The polishing cloth further is of the nature of a so-called disposable article, which can be used repeatedly after cleaning by rinsing with water until the polishing effect is being exhausted and then discarded.

The properties of the novel cleaning and polishing cloth are due to the special physical characteristics of the polishing agent employed as well as to its anchoring in the carrier material. It has been found that when synthetic oxide gels such as silica gels are used, op-

timum properties are obtained when these gels have an effective particle volume of about 0.8 to 2.9 cm lg, preferably, however, 0.9 to 1.3 cm lg. The effective particle volume results from the volume of the gel (about 0.5 cm lg at a specific weight of 2.0 to 2.1) plus the pore volume. Commercial products of this type are, for example, the RD. class of synthetic silicas Syloid 63, Syloid 64, Syloid 65, Syloid AL-l and Syloid 621 of W. R. Grace & Co., Davison Chemical Division, Baltimore, or of Grace GmbI-I, Werk Bad I-Iomburg, or the corresponding products of Joseph Crosfield & Sons, Warrington, England, sold under the trade name Gasil or Sorbsil MSH 200. Moreover, also micronized medium-porous silica gels or so-called ID. or buffer gels may be used, the preparation of which is described in the literature (see Ullmann's Enzyklopadie der technischen Chemie, 3rd Edition, Vol. 15, pages 717-721).

The granule size is in the range of about 1.5 to 60 microns; the particles of the silica of the gel type preferably having maximum diameters around 40 microns. For special applications, for example, as a silver polishing agent, narrower particle size ranges from 1.5 to 18 micron, and especially L5 to 12 micron, are preferred. These can be prepared without difficulty in a known manner from oxide gels using a fluid energy mill for decreasing the particle size as in US. Pat. No. 2,856,268.

Apart from silica gels, alumina gels are also suitable. Furthermore, mixed oxide gels such as naturally occurring argillaceous earths and silica-alumina gels may be employed.

The coating weight on the cleaning and polishing cloth after drying is suitably about 3 to 3,000 g/m and is, among others, dependent on the strength of the carrier material. The carrier may have a weight of to 100 g/m or more and be of a woven or non-woven type. Suitable carrier materials are paper, leather, textile materials and the like. Especially suitable are nonwoven fabrics of cellulose fibers or, in particular, fibers of viscose, rayon, cotton and rayon-cotton mixtures. A suitable non-woven fabric of viscose fibers has a weight of 28 to 45 glm for which a favorable coating weight is about 50 to 70 g/m. As the binding agent, a great variety of polymers can be used. These include polyacrylates, polymethacrylates, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, polyacrylic acids, polymethacrylic and polyacrylamide and other polymers having similar properties, as well as copolymers of these and other polymers. All that is essential is that the polymer or copolymer can be wetted so that it can be formulated into a dispersion. Because of the intended water-swellability, it is preferred to use aqueous dispersions of these polymers. Polyvinyl acetate emulsions or dispersions are especially suitable. The polymer or copolymer is added in an amount sufficient to anchor the silica gel, alumina gel or other oxide particle to the carrier. The amount varies with the type of carrier material, e.g., whether it is woven or nonwoven, and on the type of polymer. Generally the silica gel, alumina gel or other oxide particles are maintained in a weight ratio excess over the polymer in the impregnating dispersion.

However, a problem has existed in that the porous particles of silica and alumina gels absorb polymers for aqueous solutions or during drying of the dispersion so that their pore volume is almost completely filled. This deleteriously modifies the mechanical strength characteristics of the particles for use as a cleaning or polishing agent, and in particular the surface of the particles is changed. Further, a great portion of the binding agent is lost. Additionally, it is known that when micronized porous silica of the gel type is added to polymer solutions or dispersions, transparent closed and non-porous films are obtained after drying. This problem has been solved.

Now it has unexpectedly been found that when using certain polymers, and in particular polyvinyl acetate, a penetration and clogging of the pore structure of the silica gel particles can be avoided if the particles are first treated with ammoniated water before the binding agent is added. It is, therefore, a further subject of the present invention to set out a process for preparing the above-described novel cleaning and polishing cloth, which process is characterized in that it comprises slurrying the oxide gel with dilute aqueous ammonia solution, adding a suitable aqueous binding agent dispersion and then applying the mixture to a carrier material and drying the coated carrier material. The preferred binding agent, a polyvinyl acetate aqueous dispersion, e.g., (Mowilith DC or Mowilith DC 02 from Farbewerke Hoechst) may optionally contain a wetting agent such as polyoxymethylene ethers and/or a preservative agent such as a pentochlorophenol derivative. A preferred wetting agent is polyoxyethylene lauryl ether and a preferred preservative agent, pentachlorophenol sodium. The concentration of the dilute ammonia treating solution is suitably about 0.01 to 1.0 percent by weight.

A suitable method for checking whether a certain polymer emulsion or dispersion penetrates into the gel particles or not is the observation of the film transparency. This method comprises preparing drawdown dispersion films on black glass plates and drying at 25C. The dispersion contains about 40 percent solids and is applied to the black glass plate in a thickness of about 40 microns. The sodids are composed of parts by weight of the polymer dispersion binding agent and 13.6 parts by weight of a micronized porous silica (Syloid 72) which has an average particle size of 4 microns and a surface area of 340 m /gm. Dispersions which are suitable for the purpose of the invention yield milky films which appear to be almost incoherent. For a mere specific test of suitable dispersions, batches comprising 60 parts by weight of the porous silica gel and 40 parts by weight of the polymer dispersion are used, which are coated to a thickness of 30 microns on white cardboard and dried at C. The coatings are evaluated for their abrasion strength and with the aid of a fountain-pen for their absorption power. The presence of gel particles which are not penetrated or clogged by the polymer is indicated by a strong adsorptivity of the layer which is recognizable in strongly and broadly spreading ink lines and in the bleeding of a point of ink when in continuous contact with the tip of the fountain-pen. Further, the adsorption isotherm, as well as the capacity to be reactivated at C, prove that the pore structure of the gel has remained substantially unchanged. This indicates that the silica or alumina gel particles are not coated with the binding agent. It is only when the particles project from the binding agent that they can develop their full cleaning and polishing effect. This is due to the essentially unchanged physical properties, although being anchored in the binding agent, which is further anchored to the carrier material.

For the preparation of the cleaning and polishing cloth of the present invention, the carrier material can be coated or better impregnated throughout with the above-described mixture of of silica gel and binding agent and then dried at an elevated temperature. Any method of intimate contacting is suitable for impregnating or coating. When using a non-woven fabric as the carrier material, it has been found especially useful to carry out the impregnation during the production of the fabric and prior to calendering.

The invention is further illustrated by the following examples, but is not limited to these examples.

EXAMPLEI 23.7 gm. of a micronized silica gel (Syloid AL-l) having an effective particle volume of 0.9 em /g, surface area of 675 m lg and a granule particle size range of about 1.5 to 35 microns are dispersed in 37.1 gm of water which is ammoniated with 3.5 gm of concentrated 25 percent ammonia solution. Then "19.75 gm. of a 56 percent polyvinyl acetate dispersion (Mowilith DC 02) is added together with 18.9 percent of water, 0.1 percent of pentochloro phenyl sodium and 0.1 percent of polyoxyethylene lauryl ether.

This coating composition is used for impregnating a viscose fiber non-woven fabric having a weight of 31 g/m. For the impregnation, 170 g/m of suspension are used. After drying the impregnated fabric at about 120C, a finished product with a coating weight of 60 g/m is obtained.

This product is an excellent polishing cloth which can be used after wetting with water to clean scratchsensitive surfaces without the slightest difficulty and without any damages by scratching or the like. The cloth is especially suitable for removing insect residues from glass and paint surfaces of motorcars.

EXAMPLE The following experiment was carried out to prove that the silica gel particles are in fact not penetrated and filled by the binding agent when one works according to the process of the invention.

As in Example I, a pasty composition was prepared from 36.3 gm of water, 2 gm of a 25 percent ammonia solution, 47.1 .gm of finely divided silica gel (Syloid AL-l) and 16.4 gm. of vinyl acetate dispersion (Mowilith DC 02). This composition is spread onto two samples of the viscose non-woven fabric of Example 1 so that the coating weight after drying and activation at 125C was 1,500 and 3,000 g/m respectively, and contains 83 percent by weight of silica gel. The following table shows the adsorption values for these materials measured by gravimetric determination compared with previously activated blank silica gel samples. All samples are exposed to air streams of the respective relative humidities until their weight remains constant (isothermal balance). It is seen that the absorption capacity is substantially maintained, which indicates that the surface of the gel particles is substantially coating free and that only a minimum portion of the pore structure is occupied by the binding agent.

produced following the general procedure of Example I, but using Syloid 63, which has an average particle size of 9 microns and a surface area of 675 mlgm. This solution was impregnated into a woven cotton fabric, and the fabric dried at 120C. This cloth is an excellent cleaning cloth for removing insect and other stains from chromium plated and other surfaces after wetting with water. Further, this cloth may be cyscled, that is wetted and used, allowed to dry and rewetted and used. After ten and more cycles, the cloth was still found to be very effective.

EXAMPLE IV A pasty composition of 34 gm. of water, 2.5 gm. of 25 percent ammonia solution, 38.2 gm. of a silica gel having a surface area of 695 m lgm. and average particle size of 4.5 microns (Syloid 65) 0.1 percent pentochloro phenol sodium, 0.1 percent polyethylene lauryl ether, and 18.2 g. of a 56 percent dispersion of polyvinyl acetate in water is formulated by mixing. This composition is impregnated into a woven and a nonwoven adsorbent paper toweling. impregnation is by kneeding in the pasty composition. The towlings are then dried at C. On being wetted and used on insect spotted windshield surfaces, both towelings removed the stains, however on drying and wetting for reuse, the non-woven paper started to partially disintegrate. The woven paper toweling could be cycled and resued several times.

EXAMPLE V This example in tabular form sets out cleaning and polishing cloths. These cloths were tested on their ability to remove stains from lacquered and glass test panels. In use, the cloths are wetted and at a constant hand pressure rubbed on the soiled surface. The cloths are rated for the degree of cleaning and the ability to be reused. Table 1 sets out the data for the various cloths with E as excellent, G as good and F as fair.

What is claimed is:

l. A cleaning and polishing cloth comprising a carrier material to which a porous oxide polishing agent having a particle size of about 1.5 to 60 microns is bound by means of a water swellable polymer binding agent, said porous oxide having been pretreated with aqueous ammonia or its equivalent to prevent any substantial pore penetration by said binding agent.

2. A cleaning and polishing cloth as in claim 1 wherein said porous oxide polishing-agent is a synthetic silica having a particle volume of about 0.8 to 2.9.

3. A cleaning and polishing cloth as in claim 2 wherein said synthetic silica has a particle volume of about 0.9 to 1.3 cc/g and a particle size in the range of about 1.5 to 4 microns.

4. A cleaning and polishing cloth as in claim 2 wherein said water swellable polymer is selected from the group consisting of polyvinylacetate, polyacrylates, polymethacrylates, polyvinyl chloride and polyvinylidene chloride, and said carrier material is selected from the group consisting of paper, rayon, cotton, rayon-cottons and viscose.

5. A cleaning and polishing agent according to claim 1 wherein said porous oxide polishing agent is synthetic alumina having a particle volume of 0.8 to 2.9.

6. A cleaning and polishing agent as in claim 5 wherein said water swellable polymer is selected from the group consisting of polyvinylacetate, polyacrylates, polymethacrylates, polyvinyl chlorine and polyvinylidene chloride, and said carrier material is selected from the group consisting of paper, rayon, cotton, rayon-cottons and viscose.

7. A process for preparing a cleaning and polishing cloth comprising:

slurrying a porous oxide with aqueous ammonia or its equivalent and an aqueous dispersion of a water swellable polymeric binding agent which is substantially non-penetrating into the pores of the porous oxide;

applying this slurry to a carrier material; and

drying the composite of the carrier material coated with the slurry.

8. A method as in claim 7 wherein said porous oxide is selected from the group consisting of silicas, aluminas, aluminosilicates and argellaceous earth, and said water swellable polymeric binding agent is selected from the group consisting of polyvinylacetate, polyacrylates, polymethacrylates, polyvinyl chloride and polyvinylidene chloride.

9. A method as in claim 8 wherein said porous oxide has a particle size of about 1.5 to 60 microns and a particle volume of 0.8 to 2.9 cc/g.

10. A process as in claim 8 wherein said carrier material comprises woven and non-woven materials selected from the group consisting of papers, cottons, rayons, rayon-cottons and viscose. 

2. A cleaning and polishing cloth as in claim 1 wherein said porous oxide polishing agent is a synthetic silica having a particle volume of about 0.8 to 2.9.
 3. A cleaning and polishing cloth as in claim 2 wherein said synthetic silica has a particle volume of about 0.9 to 1.3 cc/g and a particle size in the range of about 1.5 to 4 microns.
 4. A cleaning and polishing cloth as in claim 2 wherein said water swellable polymer is selected from the group consisting of polyvinylacetate, polyacrylates, polymethacrylates, polyvinyl chloride and polyvinylidene chloride, and said carrier material is selected from the group consisting of paper, rayon, cotton, rayon-cottons and viscose.
 5. A cleaning and polishing agent according to claim 1 wherein said porous oxide polishing agent is synthetic alumina having a particle volume of 0.8 to 2.9.
 6. A cleaning and polishing agent as in claim 5 wherein said water swellable polymer is selected from the group consisting of polyvinylacetate, polyacrylates, polymethacrylates, polyvinyl chlorine and polyvinylidene chloride, and said carrier material is selected from the group consisting of paper, rayon, cotton, rayon-cottons and viscose.
 7. A process for preparing a cleaning and polishing cloth comprising: slurrying a porous oxide with aqueous ammonia or its equivalent and an aqueous dispersion of a water swellable polymeric binding agent which is substantially non-penetrating into the pores of the porous oxide; applying this slurry to a carrier material; and drying the composite of the carrier material coated with the slurry.
 8. A method as in claim 7 wherein said porous oxide is selected from the group consisting of silicas, aluminas, aluminosilicates and argellaceous earth, and said water swellable polymeric binding agent is selected from the group consisting of polyvinylacetate, polyacrylates, polymethacrylates, polyvinyl chloride and polyvinylidene chloride.
 9. A method as in claim 8 wherein said porous oxide has a particle size of about 1.5 to 60 microns and a particle volume of 0.8 to 2.9 cc/g.
 10. A process as in claim 8 wherein said carrier material comprises woven and non-woven materials selected from the group consisting of papers, cottons, rayons, rayon-cottons and viscose. 